Water at hydroxyapatite surfaces: the effect of coverage and surface termination as investigated by all-electron B3LYP-D* simulations

Adsorption of Maleic Acid Monomer on the Surface of Hydroxyapatite and TiO2: A Pathway toward Biomaterial Composites

“…The water chemisorption is favourable at both surfaces in vacuum, which agrees with previous studies. 57,71 However, the presence of solvent not only reduces the magnitude of interaction but also changes the surface receptivity. As evident from…”

Second‐order elastic constants of hexagonal hydroxylapatite (P63) fromab initioquantum mechanics: Comparison between DFT functionals and basis sets

“…In this work, a mixed ionic/covalent mineral was considered and, albeit the underestimation of the unit cell volume, the hydroxylapatite internal geometry is well depicted. This result suggests that van der Waals forces, while important in describing surface/environment processes, are not dominant in OHAp bulk.…”

Properties and Reactivity toward Water of A Type Carbonated Apatite and Hydroxyapatite Surfaces

“…This is fully justified particularly for a comparative study like the present one, as we recently showed that its role when dealing with water adsorption at HA surfaces is not crucial, as the interaction is dominated by charge-dipole interaction, well accounted for by plain B3LYP. 29 The all-electron Gaussian basis set, already used in previous related works, is as follows: 86-511G(2d) for calcium, 85-21G(d) for phosphorus, 6-31G(d) for oxygen and 6-21G(d) for carbon. [30][31][32] This methodology has already been applied to the study of mixed A-type and B-type carbonated hydroxyapatite surfaces by Ulian et al 22 Truncation criteria for the Coulomb and Hartree-Fock exchange series were set to 10 −6 (ITOL1, ITOL2, ITOL3, ITOL4) and 10 −16 (ITOL5).…”

“…Indeed, a large number of studies have applied theoretical methods to pure and substituted hydroxyapatite, both by classical molecular dynamics 19,20 and quantum-mechanical techniques. [21][22][23] In previous works some of us have simulated extensively both bulk and surface properties of HA, [24][25][26][27][28][29] and more recently the bulk properties of CAp. [30][31][32][33] The study of surfaces of biological materials is particularly relevant as these contribute to the complex interface with biological tissue and fluids.…”